<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
  <script type="text/javascript" src="js/vue-2.6.12.js"></script>
</head>
<body>

<div id="app">
<!--插值表达式-->
  <h1>{{msg}} </h1>
  <h1>{{1+2+3}}</h1>

</div>

<script>

  let vm = new Vue({

    el:"#app",
    data:{

      msg:"hello vue!"


    },

  });

</script>

</body>
</html>